Various types of generators which employ piezoelectric transducers to generate electrical potentials are known. There are, for example, the devices illustrated and described in U.S. Pat. Nos. 4,248,386 and 3,666,976 and references cited in these. Various types of generators which employ fluid flow to generate electrical potentials are also known. There are, for example, the devices illustrated and described in U.S. Pat. Nos. 4,574,092, 4,498,631, 4,433,003, 4,020,393, 3,991,710, 3,791,579, 3,673,463, and 3,651,354 (generally electrogasdynamic potential supplies); and U.S. Pat. Nos. 4,290,091 and 4,219,865 (generally gas turbine driven generator/inverter/transformer/multiplier supplies and alternator/transformer/multiplier supplies), and U.S. Ser. No. 11/500,156, filed Aug. 7, 2006, titled Electric Power Generator, and assigned to the same Assignee as this application. There is also Richard G. Goldman, Ultrasonic Technology, Reinhold Publishing Corporation, New York, 1962, and particularly pages 94-102. The disclosures of these references are hereby incorporated herein by reference. This listing is not intended to be a representation that a complete search of all relevant art has been made, or that no more pertinent art than that listed exists, or that the listed art is material to patentability. Nor should any such representation be inferred.